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An approximation to the P-wave reflection coefficient for amplitude variation with long-offset seismic data

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Applied Geophysics 2007年第1期4卷 29-36页

作者： wang Pu Zhang Wenpo Hu tianyue School of Earth and Space Sciences Peking University Beijing 100871 China Exploration and Development Research Institute Liaohe Oilfield Petrochina Liaoning 124010 China

In recent years, long-offset exploration has been widely used, especially on marine seismic surveys. Conventional AVO analysis is insufficient for long-offset seismic data. To widen the application range of AVO analysis, we present a new P-wave reflection coefficient approximation applicable to long-offset data. Our result is similar to the well known Shuey formula which can be treated as an approximation to our results for short-offset seismic data.

关键词： AVO long-offset Zoeppritz equations Poisson's ratio.

婴幼儿支气管异物的临床特征、肺部影像学及支气管镜下特点分析

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国际儿科学杂志 2015年第4期42卷 443-447页

作者：张晗张琴珍尚云晓王天玥王植嘉代冰王佳蔡栩栩韩晓华单丽沈陈宁中国医科大学附属盛京医院小儿呼吸内科沈阳110004

目的通过对30例婴幼儿支气管异物的临床特点、肺部影像学特点和异物的镜下位置、异物种类、异物对气道的刺激后黏膜的变化进行系统分析，探讨支气管异物患儿临床特征、肺部影像学、支气管镜下特点及局部麻醉下应用小儿电子纤维支气管镜... 详细信息

目的通过对30例婴幼儿支气管异物的临床特点、肺部影像学特点和异物的镜下位置、异物种类、异物对气道的刺激后黏膜的变化进行系统分析，探讨支气管异物患儿临床特征、肺部影像学、支气管镜下特点及局部麻醉下应用小儿电子纤维支气管镜（fiber bronchoscope，FBO）技术在婴幼儿支气管异物确诊和取出中优势。方法对2014年9～12月在盛京医院小儿支气管镜室应用F-t10证实并取出异物的30例患儿，年龄0—3岁，对其临床特点、肺部影像学特征以及支气管镜下特点以及取出方式进行系统性分析。结果在30例患儿中，无呛咳病史6例（20．0％），其中无咳喘症状3例（10．0％），出现咳喘症状的3例（10．O％），有明确异物呛咳史的患儿24例（80．0％），其中无咳喘症状的7例（23．3％），出现咳喘症状的17例（56．7％）。在体征方面：无呛咳病史的患儿中呼吸音正常2例（6．7％），出现喘鸣音3例（10．0％），患侧呼吸音减弱的1例（3．3％）；有呛咳病史的患儿中呼吸音正常的6例（20．0％），出现喘鸣音的12例（加．0％），患侧呼吸音减弱的6例（20．0％）；肺部影像学特点缺乏特异性表现：本组30例仅有1例显示异物，其他29例均无特异性表现，肺叶气肿13例（43．3％），是主要的影像学特点，影像学表现正常2例（6．7％）；镜下发现异物在左肺19例（63．4％），异物周围肉芽形成21例（70．0％），阻塞远端气道内黏膜坏死痰栓形成5例（16．7％）；异物吸人中位数时间4．5d[2．8，12．5]，异物吸人的时间同肉芽增生有显著相关性（R=0．688，P=0．000）。术中出现的主要不良反应：低氧6例（16．7％），一过性发热12例（40．0％），持续性发热1例（3．3％）。结论经FBO局部麻醉下对儿童异物的诊断较其他方法准确率高，并且经FBO局部麻醉下进行支气管异物取出术是一种安伞、有效的方法．

关键词：儿童纤维支气管镜支气管异物局部麻醉

Loss induced negative refraction and super-prism effect at highly absorptive interface

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Chinese Physics B 2019年第5期28卷 101-105页

作者： Jian Wu Tao wang tianyue Hou Xuefen Kan Cheng Yin Pu Zhou Zhuangqi Cao College of Advanced Interdisciplinary Studies National University of Defense Technology Hunan Provincial Key Laboratory of High Energy Laser Technology Jiangsu Key Laboratory of Power Transmission and Distribution Equipment Technology Hohai University College of Physics and Astronomy Shanghai Jiao Tong University

It is well-established that waves are inhomogeneous in a lossy isotropic medium, and the validation of the classical Snell's law is still questionable for light refraction at the dissipative and dispersive interface. With high absorption, direct experimental investigation is rather difficult due to the extremely short penetration depth; i.e., the skin depth. In this paper, a simple and unified description of this issue is proposed, which can be applied to both materials with anomalous dispersion and in the Drude region. The gradient ▽_k~ω is found to be incident angle θ_i-dependent, and the direction of the group velocity may deviate significantly from the phase velocity due to the loss induced permittivity structure. The physics behind the negative refraction effect is explained, and a novel loss induced super-prism effect is also predicted.

关键词： Snell’s Law Drude model anomalous dispersion lossy isotropic media

原发性失眠局部脑区功能变化的静息态功能磁共振成像研究

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功能与分子医学影像学（电子版） 2015年第4期4卷 7-12页

作者：曾少庆黎程江桂华汪天悦詹文峰尹毅华克磊刘倩傅世舜广东省第二人民医院影像科广州510317

目的探讨原发性失眠(PI)患者静息状态下全脑范围内局部脑功能磁共振成像特点。方法对59例PI患者及47例年龄、性别和受教育程度均与之匹配的健康对照者进行静息态功能磁共振成像扫描。应用局部一致性分析方法,得出PI患者局部一致性(Re Ho... 详细信息

目的探讨原发性失眠(PI)患者静息状态下全脑范围内局部脑功能磁共振成像特点。方法对59例PI患者及47例年龄、性别和受教育程度均与之匹配的健康对照者进行静息态功能磁共振成像扫描。应用局部一致性分析方法,得出PI患者局部一致性(Re Ho)异常的脑区。结果与正常对照组相比,在静息状态下PI患者左侧脑岛、右侧前扣带回、双侧中央前回、左侧楔叶局部一致性升高;而在右侧扣带中回、左侧梭状回局部一致性降低。结论静息状态下PI患者存在情绪、感觉运动区域等多个脑区的局部功能活动的异常,从功能分化的角度探究PI患者大脑神经活动的改变,有利于进一步理解PI的神经活动特点。

关键词：局部一致性静息态磁共振原发性失眠

Formation of the Zengmu and Beikang Basins,and West Baram Line in the southwestern South China Sea margin

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Journal of Oceanology and Limnology 2023年第2期41卷 592-611页

作者： Bing HAN Zhongxian ZHAO Xiaofang wang Zhen SUN Fucheng LI Benduo ZHU Yongjian YAO Liqiang LIU tianyue PENG Genyuan LONG Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 511458China Key Laboratory of Marine Mineral Resources Ministry of Natural ResourcesGuangzhou 511458China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Guangzhou Marine Geological Survey China Geological SurveyMinistry of Natural ResourcesGuangzhou 511458China University of Chinese Academy of Sciences Beijing 100049China Hainan Key Laboratory of Marine Geological Resources and Environment Haikou 570206China

The Zengmu and Beikang basins,separated by the West Baram Line(WBL)in the southwestern South China Sea margin,display distinct geological and geophysical ***,the nature of the basins and the WBL are *** we explore this issue by conducting the stratigraphic and structural interpretation,faults and subsidence analysis,and lithospheric finite extension modelling using seismic *** show that the WBL is a trans-extensional fault zone comprising normal faults and flower structures mainly active in the Late Eocene to Early *** Zengmu Basin,to the southwest of the WBL,shows an overall synformal geometry,thick folded strata in the Late Eocene to Late Miocene(40.4-5.2 Ma),and pretty small normal faults at the basin edge,which imply that the Zengmu Basin is a foreland basin under the Luconia and Borneo collision in the Sarawak since the ***,the basin exhibits two stages of subsidence(fast in 40.4-30 Ma and slow in 30-0 Ma);but the amount of observed subsidence and heat flow are both greater than that predicted by crustal *** Beikang Basin,to the NE of the WBL,consists of the syn-rift faulted sub-basins(45-16.4 Ma)and the post-rift less deformed sequences(16.4-0 Ma).The heat flow(~60 mW/m2)is also consistent with that predicted based on crustal thinning,inferring that it is a rifted ***,the basin shows three stages of subsidence(fast in 45-30 Ma,uplift in 30-16.4 Ma,and fast in 16.4-0 Ma).In the uplift stage,the strata were partly folded in the Late Oligocene and partly eroded in the Early Miocene,which is probably caused by the flexural bulging in response to the paleo-South China Sea subduction and the subsequent Dangerous Grounds and Borneo collision in the Sabah to the east of the WBL.

关键词： tectonic subsidence foreland basin West Baram Line Zengmu Basin Beikang Basin South China Sea

Dependence of interface energetics and kinetics on catalyst loading in a photoelectrochemical system

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Nano Research 2019年第9期12卷 2378-2384页

作者： Yumin He Srin ivas Vanka tianyue Gao Da He Jeremy Espano Yanyan Zhao Qi Dong Chaochao Lang Yongjie wang Thomas W. Hamann Zetian Mi Dunwei wang Department of Chemistry Merkert Chemistry CenterBoston College2609 Beacon StreetChestnut HillMassachusetts 02467USA Department of Electrical Engineering and Computer Science University of Michigan1301 Beal AvenueAnn ArborMichigan 48109USA Department of Chemistry Michigan State UniversityEast LansingMichigan 48824USA Department of Electrical and Computer Engineering McGill University3480 University StreetMontrealQuebecH3A 0E9Canada

Solar hydrogen production by the photoelectrochemical method promises a means to store solar *** it is generally understood that the process is highly sensitive to the nature of the interface between the semiconductor and the electrolyte,a detailed understanding of this interface is still *** instance,few prior studies have established a clear relationship between the interface energetics and the catalyst loading *** we aim to study this relationship on a prototypical Si-based photoelectrochemical *** types of interfaces were examined,one with GaN nanowires as a protection layer and one *** was found that when GaN was present,higher Pt loading (> 0.1 μg/cm2) led to not only better water reduction (and,hence,hydrogen evolution) kinetics but also more favorable interface energetics for greater *** the absence of the protection layer,by stark contrast,increased Pt loading exhibited no measurable influence on the interface energetics,and the main difference was observed only in the hydrogen evolution *** study sheds new light on the importance of interface engineering for further improvement of photoelectrochemical systems,especially concerning the role of catalysts and protection layers.

关键词： photoelectrochemistry water splitt ing Si hydroge n evolutio n catalyst nano wires

Integrating the optical tweezers and spanner onto an individual single-layer metasurface

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Photonics Research 2021年第6期9卷 1062-1068页

作者： tianyue LI XIAOHAO XU BOYAN FU SHUMING wang BAOJUN LI ZHENLIN wang SHINING ZHU National Laboratory of Solid-State Microstructures School of PhysicsCollege of Engineering and Applied SciencesNanjing UniversityNanjing 210093China Institute of Nanophotonics Jinan UniversityGuangzhou 511443China Key Laboratory of Intelligent Optical Sensing and Manipulation Ministry of EducationNanjing 210093China

Optical tweezers(OTs)and optical spanners(OSs)are powerful tools of optical manipulation,which are responsible for particle trapping and rotation,***,the OT and OS are built using bulky three-dimensional devices,such as microscope objectives and spatial light ***,metasurfaces are proposed for setting up them on a microscale platform,which greatly miniaturizes the ***,the realization of both OT and OS with one identical metasurface is posing a ***,we offer a metasurface-based solution to integrate the OT and *** the prevailing approach based on geometric and dynamic phases,we show that it is possible to construct an output field,which promises a high-numerical-aperture focal spot,accompanied with a coaxial *** trapping and rotation are numerically demonstrated by estimating the mechanical effects on a particle ***,we demonstrate an on-demand control of the OT-to-OS distance and the topological charge possessed by the *** revealing the OT–OS metasurfaces,our results may empower advanced applications in on-chip particle manipulation.

关键词： surface trapping optical

不同西瓜种植规模下农户对先进技术选择的行为差异

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贵州农业科学 2019年第7期47卷 159-163页

作者：石保纬梁盛凯王田月陆泉志陆宇明范稚莲莫良玉广西大学农学院广西南宁530004 广西农业科学院园艺研究所广西南宁530007 广西经济管理干部学院广西南宁530007 广西农业科学院广西南宁530007 广西大学新农村发展研究院广西南宁530004

提高先进技术推广效率,为推进西瓜产业高质量发展提供参考依据,以西瓜种植规模为因子,结合对广东和广西334份农户种植西瓜的调查情况,利用单因素分析模型实证分析不同种植规模下西瓜种植户对先进技术选择的差异性。结果表明:不同规模西... 详细信息

提高先进技术推广效率,为推进西瓜产业高质量发展提供参考依据,以西瓜种植规模为因子,结合对广东和广西334份农户种植西瓜的调查情况,利用单因素分析模型实证分析不同种植规模下西瓜种植户对先进技术选择的差异性。结果表明:不同规模西瓜种植农户对先进技术的选择存在显著差异,种植规模在0.67~66.67 hm^2的农户对先进技术有更高的选择率;种植规模在66.67 hm^2以上农户的经济效益最低。随着农户西瓜种植规模的递增,其对先进技术的选择呈“倒U”形,不断扩大种植规模并不能提升农户对先进技术的选择。针对农户先进技术选择率低的问题,建议通过降低先进技术的使用成本,提升农户对先进技术选择;加强对农户的先进技术指导,提高农户专业技术水平;加大力度鼓励技术创新,推动农业转型;合理规划种植面积,提高农户经济效益。

关键词：种植规模行为差异技术选择经济效益

Comprehensive investigation on producing high-power orbital angular momentum beams by coherent combining technology

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High Power Laser Science and Engineering 2019年第2期7卷 88-96页

作者： Dong Zhi tianyue Hou Pengfei Ma Yanxing Ma Pu Zhou Rumao Tao Xiaolin wang Lei Si College of Advanced Interdisciplinary Studies.National University cf Defense Technology Changsha 410073China Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000.China

High-power orbital angular momentum(OAM)beams have distinct advantages in improving capacity and data receiving for free-space optical communication systems at long *** the coherent combination of a beam array technique and helical phase approximation by a piston phase array,we have proposed a generating system for a novel high-power beam carrying OAM,which could overcome the power limitations of a common vortex phase modulator and a single *** characteristics of this generating method and the orthogonality of the generated OAM beams with different eigenstates have been theoretically analyzed and *** a high-power OAM beam produced by coherent beam combination(CBC)of a six-element hexagonal fiber amplifier array has been experimentally *** show that the CBC technique utilized to control the piston phase differences among the array beams has a high efficiency of 96.3%.On the premise of CBC,we have obtained novel vortex beams carrying OAM of±1 by applying an additional piston phase array modulation on the corresponding beam *** experimental results agree approximately with the theoretical *** work could be beneficial to areas that need high-power OAM beams,such as ultra-long distance free-space optical communications,biomedical treatments,and powerful trapping and manipulation under deep potential wells.

关键词： orbital angular momentum beams coherent beam combination